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From: konsolebox <konsolebox@gmail.com>
Newsgroups: gnu.bash.bug
Subject: Re: Assignment of associative arrays through braces
Date: Wed, 1 Aug 2018 00:53:38 +0800
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Approved: bug-bash@gnu.org
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Cc: bug-bash <bug-bash@gnu.org>
To: Chester Ramey <chet.ramey@case.edu>
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On Tue, Jul 31, 2018 at 10:31 PM, Chet Ramey <chet.ramey@case.edu> wrote:
> On 7/27/18 7:13 PM, konsolebox wrote:
>> Hi Chet,
>>
>> I wonder if you can allow bash to have another syntax to allow simpler
>> declaration and/or definition of associative arrays.  The changes
>> needed to have it done seem simple enough, and the only conflict it
>> makes is a scalar `var={...` assignment, which in my opinion is better
>> quoted to make it more readable and less questionable from other
>> syntaxes like brace expansion.  I believe most people intuitively
>> quotes it, and assignments that start with `{` is fairly rare.
>
> So it's syntactic sugar for `declare -gA a; a=( ... )'?

That surely is one of the main goals, but it's not exact.  `declare
-gA a; a=(...)` would always affect the main global scope.

Example:

$ g() { declare -gA a=([x]=y); }; f() { local -A a=(); g; declare -p
a; }; declare -A a=([a]=b); f; declare -p a
declare -A a=()
declare -A a=([x]="y" )

But as shown in my earlier example, a={...} would only affect the
nearest scope which was local a={}.

This proposal simply requests an intuitively equivalent simple
assignment syntax for associative arrays just like a='...' and
a=(...), with same behavior for scoping.

Maybe we can add another option like -G to have similar effect but
that's a little different already.  Just allowing a={} would make it
simpler for every scripter.

-- 
konsolebox